初始提交: Gitea 项目代码

modules/svg/svg.go

@@ -0,0 +1,133 @@
+// Copyright 2020 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package svg
+
+import (
+	"fmt"
+	"html/template"
+	"path"
+	"strings"
+	"sync"
+
+	gitea_html "gitea.dev/modules/htmlutil"
+	"gitea.dev/modules/log"
+	"gitea.dev/modules/public"
+)
+
+type svgIconItem struct {
+	html    string
+	mocking bool
+}
+
+type svgCacheKey struct {
+	icon  string
+	size  int
+	class string
+}
+
+var (
+	svgIcons map[string]svgIconItem
+
+	svgCacheMu    sync.Mutex
+	svgCache      sync.Map
+	svgCacheCount int
+	svgCacheLimit = 10000
+)
+
+const defaultSize = 16
+
+// Init discovers SVG icons and populates the `svgIcons` variable
+func Init() error {
+	const svgAssetsPath = "assets/img/svg"
+	files, err := public.AssetFS().ListFiles(svgAssetsPath)
+	if err != nil {
+		return err
+	}
+
+	svgIcons = make(map[string]svgIconItem, len(files))
+	for _, file := range files {
+		if path.Ext(file) != ".svg" {
+			continue
+		}
+		bs, err := public.AssetFS().ReadFile(svgAssetsPath, file)
+		if err != nil {
+			log.Error("Failed to read SVG file %s: %v", file, err)
+		} else {
+			svgIcons[file[:len(file)-4]] = svgIconItem{html: string(Normalize(bs, defaultSize))}
+		}
+	}
+	return nil
+}
+
+func MockIcon(icon string) func() {
+	if svgIcons == nil {
+		svgIcons = make(map[string]svgIconItem)
+	}
+	orig, exist := svgIcons[icon]
+	svgIcons[icon] = svgIconItem{
+		html:    fmt.Sprintf(`<svg class="svg %s" width="%d" height="%d"></svg>`, icon, defaultSize, defaultSize),
+		mocking: true,
+	}
+	return func() {
+		if exist {
+			svgIcons[icon] = orig
+		} else {
+			delete(svgIcons, icon)
+		}
+	}
+}
+
+// RenderHTML renders icons - arguments icon name (string), size (int), class (string)
+func RenderHTML(icon string, others ...any) template.HTML {
+	result, _ := renderHTML(icon, others...)
+	return result
+}
+
+func renderHTML(icon string, others ...any) (_ template.HTML, usingCache bool) {
+	if icon == "" {
+		return "", false
+	}
+	size, class := gitea_html.ParseSizeAndClass(defaultSize, "", others...)
+	if svgItem, ok := svgIcons[icon]; ok {
+		svgStr := svgItem.html
+		// fast path for default size and no classes
+		if size == defaultSize && class == "" {
+			return template.HTML(svgStr), false
+		}
+
+		cacheKey := svgCacheKey{icon, size, class}
+		cachedHTML, cached := svgCache.Load(cacheKey)
+		if cached && !svgItem.mocking {
+			return cachedHTML.(template.HTML), true
+		}
+
+		// the code is somewhat hacky, but it just works, because the SVG contents are all normalized
+		if size != defaultSize {
+			svgStr = strings.Replace(svgStr, fmt.Sprintf(`width="%d"`, defaultSize), fmt.Sprintf(`width="%d"`, size), 1)
+			svgStr = strings.Replace(svgStr, fmt.Sprintf(`height="%d"`, defaultSize), fmt.Sprintf(`height="%d"`, size), 1)
+		}
+		if class != "" {
+			svgStr = strings.Replace(svgStr, `class="`, fmt.Sprintf(`class="%s `, class), 1)
+		}
+		result := template.HTML(svgStr)
+
+		if !svgItem.mocking {
+			// no need to double-check, the rendering is fast enough and the cache is just an optimization
+			svgCacheMu.Lock()
+			if svgCacheCount >= svgCacheLimit {
+				svgCache.Clear()
+				svgCacheCount = 0
+			}
+			svgCacheCount++
+			svgCache.Store(cacheKey, result)
+			svgCacheMu.Unlock()
+		}
+
+		return result, false
+	}
+
+	// during test (or something wrong happens), there is no SVG loaded, so use a dummy span to tell that the icon is missing
+	dummy := template.HTML(fmt.Sprintf("<span>%s(%d/%s)</span>", template.HTMLEscapeString(icon), size, template.HTMLEscapeString(class)))
+	return dummy, false
+}